A man the other day told me that if I ride even even single speed gears, like 32/14 or 34/16 then I would be using the same two spots in my chain, thus wearing it out way faster than normal. It makes sense, maybe if you are running even gears, and have a quick link, watch the quick link seeing where it is at during the down stroke on each side. It will be in the same spot.
I'm 99% sure going to do magic gear again. check it out.
I did it last year, 34/16 on a 425mm chainstay and it worked great. By the end of the season, the chain was stretched. I think this year I will carefully take the chain off the front sprocket every 2 weeks, rotate the arm quarter turn, and reinstall the chain. It will be an easy thing to do to offset chain wear. Since none of the magic gears have an even odd combo like 42/19 or 38/17 or 34/15 you will wear your chain out of you don't do it.
34/16 is pretty easy for fast cx racing. If you have the same 425 chainstay, like 90% off cross bikes do, then 32/14 is another option, its a bit heavier, and if you race the open race after the ss, you'll wish you had the easier gears.